Corn gluten plastic and method of making same



Patented Jan. 22, 1935 I I Henry Berlin, New York, N. Y., assignor, by mesnc assignments, to Resinox Corporation, New York, N. Y., a corporation of Delaware No Drawing. Application February 20, 1931, Serial No. 517,319

1 Claim. (01. 106-22) This invention relates to the utilization of a hours or, by (4) being kept in an aqueous solupurified form of corn gluten for the production tion of formaldehyde for a suitable length of time of dense, hard, hom-like substances. While the which may vary from twelve hours or less to physical properties of the substances produced several weeks, and then dried. Or the articles may vary in accordance with regulated variations made under (1), (2) or (3) may be (5) im-' 5 (within the scope of my invention) in the process mersed in a bath of casein, sodium hydroxide ,of manufacture, the products in respect to their and formaline for periods of time from about general physical characteristics are similar to twelve hours to several weeks; the period of treatand may be said to be intermediate casein plasment under (4) or (5) varying in accordance tics and synthetic resins of the phenol-formaldewith the size and also the shape or surface con- 10 hyde type (bakelite). They are stronger and tour of the article. more heat resistant than casein plastics and can Finally, articles made as above may be dyed be made to take colors better than bakelite. (6) with mineral dyes which are added to the They are substantially as hard but are less brittle batches of processesu) (2) or (3); or (7). with and somewhat more flexible than bakelite and organic dyes in which case the articles made 15 can be more successfully machine or sculptured. under processes (1) to (5) -but without drying The corn gluten used preferably comprises a if made under (4) or (5)-are first immersed in purified mixture containing both the alcohol solua lead acetate bath and then in an acid bath, ble portion and the alcohol insoluble portion, alhydrochloric acid, for example. The lead ace- -though these materials may be employed septate will penetrate the plastic substance to some 20 arately. It should be substantially free of fats, extent and will react with the hydrochloric acid which cause blistering in the molds, and of starch to precipitate lead chloride, which is a substance which tends to make the product brittle and whiteincolor. This providesasurfacefilmthat non-resistant to water. To obtain gluten of the will combine with the' organic dye to give a lake.

- required purity, crude corn gluten from the gluten In this method ('7) either natural or synthetic 25 settlers may be treated in accordance with any organic (fires may be employed. The process may of the methods disclosed in the co-pending U. S. also be used for dyeing other plastics such application of Henry Berlin, filed July 19, 1929, those of the casein type. Serial No. 379,563, now U. S. Patent 1,888,785. Specific procedures in accordance with this 80 For example, according to one procedure disinvention are givenin the following examples: o

' closed in this patent, crude gluten is treated with Example (1) cresol to obtain a purified material which may subsequently be separated into its component 100 parts by weight of finely powdered, starch parts, prolamin and glutelin. The purified mixand fat free corn gluten (both soluble and inture, consisting principally of prolamin and solublein alcohol).or of the soluble portion (pro- 35 glutelin, is particularly adapted for use in the lamin) or of the insoluble portion (glutelin), are present process. thoroughly mixed, cold, with 8 parts of carbolic In addition to gluten the process involves the acid, 3 of butanol, 2.5 parts of glycerine, 3 parts use of (1) a phenolic substance, one or several of hexamethylenetetramine,2.-5 parts paraformal- 40 higher alcohols and small amounts of formaldedehyde and 5 Parts Of water. and the mixture 40 hyde or polymers thereof, or condensates capable molded at 300 F. and 3000 pounds pressure for of liberating formaldehyde; or (2) aheterocyclic nine minutes. The higher alcohols, butanol and aldehyde such as furfural and an aromatic ester glycerlne, can be used alternatively but are prefsuch as di-or mono-ethylphthalate; or (3) the erably both employed. The glycerine will be substances mentioned under (1) together with found to remain in the product to some extent 45 those specified under (2) v and therefore to increase its plasticity. The bu- The ingredients are mixed, with or without tanol is a wetting agent primarily and to a large water added as a diluent (which, if added, must extentcvaporates. Higher alcohols are used in be removed by drying before molding) and this preference to lower alcohols because of their mixture is molded in molds, such as are used for higher boiling pointsin view of the temperatures 50 bakelite or phenol carbohydrate resins or shelof the molding or curing operation. Other highlac resins, with application of heat and pressure. er alcohols could be used such as di-acetone alco- The molded articles are dense and hard but they hol. The alcohols are primarily used to give penemay be further hardened and made water retration and facilitate the plasticizing or condenssistant by baking in an oven at C. for. 24 ing action of the gluten and phenolic substance. 55

maldehyde could be used in place of the specified hexamethylenetetramine and paraformaldehyde except that as a gas or in its liquid solution (formaline) it is diflicult to handle. Preferably both hexamethylenetetramine and paraformaldehyde are used because the former decomposes at a higher temperature than the latter, that is, one decomposes too soon at the temperature of molding and the other too late, so that by using both these formaldehyde yielding substances formaldehyde is left in contact with the other ingredicuts in suiflcient amounts, without undue waste, and for a sufliciently longtime to insure the necessary hardening action. Water is not essential but facilitates interpenetration in mixing the ingredients of the bath. The temperature should be high enough to decompose the formaldehyde yielding substances but not high enough to char the gluten, approximate range 250 F. to 300 F. The pressure should be as highas possible toinsure high density in the molded article.

Example (2) The furfural and di-ethylphthalate of Example (2) can be added to the ingredients of Example (1) and the amount of gluten doubled. Molding will be in accordance with Example (1) Example (4) Hardening and waterproofing The product of Example (1) or-(2) or (3) is put intoa 40% aqueous solution of formaldehyde and left for from twelve hours to several weeks depending on the size and shape of the article.

Example (5) The molded article may be immersed for like periods of time in a bath consisting of 1000 parts by weight of water, 100 parts casein, 1.5 parts of sodium hydroxide and 20 parts of a 40% solution of formaldehyde.

Example (6) Dyeing When mineral dyes are used they are incorporated into the batches of processes (1), (2) or (3) and when organic dyes are to be used.

Example (7) The articles of processes (1) to (5)the drying step being omitted in case the water proofing step of Examples (4.) or (5) is employed-are immersed first in a bath consisting of a. 10% water solution of lead acetate and then in a bath consisting of a 10% solution of hydrochloric acid, and as soon as the surface is coated with lead chloride the article is taken out of the bath and rinsed with water toremove the acid and put into the dye vat where the dye and lead chloride combine to form a water insoluble lake which adheres to the molded article.

I desire to cover by patent all modifications of the above specific processes within the scope of the appended claim.

I claim:

A heat hardened reaction product of a phenolic substance. an aldehyde-yielding substance, and the residue of corn gluten, after substantially complete removal of itsfat and starch content, consisting principally of prolamin and glutelin.

HENRY BERLm 

